1. Field of the Invention
The subject invention generally pertains to fabric air ducts and more specifically to a vent for such a duct.
2. Description of Related Art
HVAC systems (heating, ventilating and air conditioning systems) often include a network of sheet metal air ducts for conveying conditioned air through a building. The ductwork often includes several registers for discharging the air into certain rooms or areas within the building. To balance the distribution of airflow throughout the building, each register may include a damper for adjusting the amount or direction of airflow through individual registers. Currently, there is a wide assortment of registers and dampers that are readily available for use on ductwork made of sheet metal.
Sheet metal, however, is not necessarily the best material for air ducts. In many applications, such as food-processing facilities, the ducts are preferably made of a fabric or other type of pliable, non-corrosive material. Fabric and other pliable materials are often preferred when cleanliness, even air dispersion, condensation control, or appearance is a significant concern.
Unfortunately, conventional metal dampers and register are not readily incorporated into fabric ductwork. Metal hardware can be difficult to attach to fabric, the weight of the metal may pull and tear on fabric, and metal registers would most likely need to be removed before a fabric duct could be machined washed.
Some adjustable registers, nonetheless, have been designed specifically for use with fabric air ducts. An example of such a register is disclosed in U. S. Pat. No. 6,280,320. In this example, the register includes an elongate member that can be slid lengthwise to adjust the volume of air discharged from the duct. Although effective for its intended purpose, the volume of air through the register is substantially uniform over its entire length, and the register cannot adjust the direction of airflow.
To avoid creating an uncomfortable draft or to avoid discharging air directly against food products, in some cases it may be more desirable to redirect the airflow or to block off certain portions of it rather than to restrict the airflow along the entire length of the register. Thus, there is a need for providing fabric air ducts with a register that can change the volume and direction of airflow and perhaps do so at various locations along the length of the register.